Could you check the Archive job's joblog and see if anything has been archived in the archive job run. The archive job maybe successful but if it does not find any data that matches the archive rules created then i may not archive anything and thus not show anything in the restore view.

When you checked the event viwer, did you also check the Enterprise Vault Event viewer. Just like the Application and System event logs there are also specific event logs for Enterprise Vault which powers BEAO, have you checked if there are any events in teh EV specific event viewer?

THe best way to do it is to go to the "Restore from Archives" option, click somewhere on the restore job window and then check the EV event viewer.